Carnot Cycle: Summary

The answers to the ConcepTests are given below and will open in a separate window. 
Key points from this module:
  • The entropy change of the Carnot engine or heat pump is zero because it runs in a continuous cycle.
  • The Carnot engine yields the most work that can be obtained for heat transfer between a high and low temperature reservoir.
  • The Carnot heat pump is the Carnot engine, but run in reverse.
From studying this module, you should now be able to:
  • Sketch the Carnot cycle on a temperature-entropy (T-S) or a pressure-volume (P-V) diagram.
  • Calculate heat added, heat removed, or work for a Carnot cycle, and the thermal efficiency.
  • Explain how thermal efficiency changes as the high and low temperatures for a Carnot cycle change.
  • Calculate the coefficient of performance (COP) for a Carnot heat pump.
  • Explain how COP changes as the high and low temperatures of a Carnot cycle change.

Prepared by John L. Falconer, Department of Chemical and Biological Engineering, University of Colorado Boulder